The concentration of acetate was determined in the hepatic and peripheral blood of 10 chronic alcoholics and six healthy non-alcoholic controls after a peroral dose of ethanol (0.8 g/kg b.wt.). The blood acetate concentration was significantly higher in the hepatic vein than peripherally and remained at a rather constant level both in alcoholics and controls during the course of ethanol elimination. However, the level of acetate was significantly (p less than 0.005) higher in alcoholics than in controls both in the hepatic vein (1.79 and 1.15 mM) and peripherally (0.91 and 0.52 mM) (alcoholics and controls respectively). The alcoholics also eliminated ethanol 54% faster than the controls (159 mg/kg b.wt./hr and 103 mg/kg b.wt./hr; alcoholics and controls respectively). Furthermore a highly significant correlation was found between the rate of ethanol elimination and blood acetate level both in the hepatic (r = 0.877, p less than 0.001) and in the peripheral vein (r = 0.799, p less than 0.001). Our results suggest that an increased level of blood acetate during ethanol oxidation may be used as an indicator of enhanced ethanol elimination.